Network Automation using udp 40125

Posts: 4
4380     0


i'm installing a network automation (6.7.3) on one of my customers.

i noticed in the firewall that there is traffic from network automation on udp 40125 to some of the devices.

i tried to find over the internet for what this port is using but i didn't find anything helpfull.


do you know what is the purpose of this port?

NMAP defaults to UDP 40125

Posts: 244
4381     0

I think this explains it -- NetMRI uses NMAP for port scanning.  And NMAP defaults to UDP port 40125 for UDP-based host discovery.  See the doc at

Re: NMAP defaults to UDP 40125

Posts: 82
4381     0

proper link:


Check out our new Tech docs website at for latest documentation on Infoblox products.

Re: NMAP defaults to UDP 40125

Posts: 32
4381     0


Wow, this may be a new record for the oldest thread to come back to life -- over three years!  :-)


As you guessed, UDP port 40125 is used by nmap.  It is used during device discovery, as part of NetMRI's process for "guessing" SNMP credentials.  It is used specifically when NetMRI has been unable to guess working SNMP credentials, as part of a check for IP "reachability" that's a bit more reliable than a simple ICMP ping.


Showing results for 
Search instead for 
Did you mean: 

Recommended for You